In the wwstore module you can do this now I think.  You would set up a hidden page drop the store admin module there, setup your categories first then add your products. 

On a "Store" page add the wwstoremenu - to the left pane , then the Storefront to contentpane.  The store menu will show your  categories automatically and the Storefront wil default to showing featured category.  In the Storefront settings menu go the the Catalog Settings menu - check  Show Category Products Show Category Message only.  In the Category Product Settings uncheck the Show Purchase Link. 

I think that will get you what you want.